Locally adminstered mac address based method for selectively and efficiently identifying enhanced version nodes of standards

ABSTRACT

Embodiments of the invention provide a method for selectively identifying nodes implemented enhanced version of a protocol standard by creating a random locally administered MAC address and advertising said random locally administered MAC address as the address that implies a particular protocol amendment of a protocol standard.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and incorporates by reference U.S.application Ser. No. 11/565,921 filed on Dec. 1, 2006 said applicationclaims priority to and incorporates by reference U.S. ProvisionalApplication No. 60/741,928, filed Dec. 2, 2005, entitled “Locallyadministered MAC address based method for selectively and efficientlyidentifying enhanced version nodes of Institute of IEEE 802 standards,”Shantanu Kangude and Harshal Chhaya inventors and U.S. ProvisionalApplication No. 60/742,246, filed Dec. 5, 2005, entitled “Methods forsilencing all 802.11 WLAN nodes in a neighborhood but selectivelyexcluding those belonging to a particular amendment enhancement,”Shantanu Kangude and Harshal Chhaya inventors.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

BACKGROUND

Embodiments of the invention are directed, in general, to communicationsystems and, more specifically, to identifying enhanced version nodes incommunication systems.

As newer and newer amendments of standards (like Institute of Electricaland Electronics Engineers (IEEE) 802.11n high throughput and 802.11smesh networking, for example) are standardized, network scenarios withsuch enhanced nodes co-existing with legacy nodes will be abundant.Newer amendments of standardized protocols can usually operatesignificantly more efficiently in the absence of legacy nodes. Also,newer amendments can employ advanced mechanisms if they can identifynodes that support the techniques defined in the amendments. Thus,identifying legacy nodes and nodes supporting various differentamendments is important to ensure optimum performance in a network.Additionally, newer amendments like 802.11s mesh can employ advancedmechanisms such as congestion control or reservations if they cansilence legacy STAtions (STA)s selectively for a certain duration intime. Selectively silencing or selectively excluding the silencing of aparticular class of nodes may be useful in other cases as well. Forexample, to ensure access or no access for a particular class forfairness policies etc.

In IEEE 802.11 protocol, Silencing of nodes is achieved by setting theirNetwork Allocation Vector (NAV)s to certain duration. The challenge isto set the NAV of a particular group/class of nodes. Even if a packetachieves such selective silencing, a further issue is that the nodesthat are not silenced can update the NAVs of the silenced nodes and getthem out of their silence mode. Such a behavior is prescribed in 802.11eas NAV may be shorted by transmitting nodes when they end theirtransmission opportunity (TXOP)s. A TXOP is defined by the start timeand a maximum duration.

Thus, there is a need to identify legacy nodes and selectively silencingthese nodes.

SUMMARY

Embodiments of the invention provide a method for selectivelyidentifying nodes implementing enhanced version of a standard bycreating a random locally administered MAC address and advertising thesaid random locally administered MAC address as the address that impliesa particular amendment of a standard.

Also provided is a method to achieve selective silencing of a particularclass of nodes and continued contention based access by the remainingnodes for the period of selective silencing.

These and other features and advantages will be more clearly understoodfrom the following detailed description taken in conjunction with theaccompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosure and the advantagesthereof, reference is now made to the following brief description, takenin connection with the accompanying drawings and detailed description,wherein like reference numerals represent like parts.

FIG. 1 is a functional block diagram generally illustrative of awireless system which may use an embodiment of the invention.

FIG. 2 is a functional block diagram illustrative of an exemplary datapacket used for wireless data transmission.

FIG. 3 is method for method for identifying enhanced version nodes inaccordance with an embodiment of the invention.

FIG. 4 is method for selectively silencing nodes or causing a controlframe induced action in accordance with an embodiment of the invention.

FIG. 5 is a block diagram of a representative example of a mobile deviceemploying principles of the invention.

DETAILED DESCRIPTION

It should be understood at the outset that although an exemplaryimplementation of one embodiment of the disclosure is illustrated below,the system may be implemented using any number of techniques, whethercurrently known or in existence. The disclosure should in no way belimited to the exemplary implementations, drawings, and techniquesillustrated below, including the exemplary design and implementationillustrated and described herein, but may be modified within the scopeof the appended claims along with their full scope of equivalents.

System may include many more components than those shown. Generally,nodes may include any device capable of connecting to a wired orwireless network. Such devices include cellular telephones, smartphones, pagers, radio frequency (RF) devices, infrared (IR) devices,integrated devices combining one or more of the preceding devices, andthe like. Nodes may also include other devices that have a wirelessinterface, such as Personal Digital Assistants (PDAs), handheldcomputers, personal computers, multiprocessor systems,microprocessor-based or programmable consumer electronics, network PCs,wearable computers, and the like.

LANs can employ any form of computer readable media for communicatinginformation from one electronic device to another. LANs can includedirect connections, such as through a universal serial bus (USB) port,other forms of computer-readable media, or any combination thereof.Links within LANs typically include fiber, twisted wire pair or coaxialcable, while links between networks may utilize analog telephone lines,full or fractional dedicated digital lines including T1, T2, T3, and T4,Integrated Services Digital Networks (ISDNs), Digital Subscriber Lines(DSLs), wireless links including satellite links, fiber, AsymmetricDigital Subscriber Lines (ADSL), Video Digital Subscriber Lines (VDSL),or other link known to those skilled in the art. Furthermore, remotecomputers and other related electronic devices can be remotely connectedto either LANs or Wide Area Networks (WANs) via a modem and temporarytelephone link.

The media used to transmit information in the links illustrates one typeof computer-readable media, namely communication media. Generally,computer-readable media includes any media that can be accessed by acomputing device. Communication media typically embodiescomputer-readable instructions, data structures, program modules, orother data in a modulated data signal such as a carrier wave or othertransport mechanism and includes any information delivery media. Theterm “modulated data signal” means a signal that has one or more of itscharacteristics set or changed in such a manner as to encode informationin the signal. By way of example, communication media includes wiredmedia such as twisted pair, coaxial cable, fiber optics, wave guides,and other wired media and wireless media such as acoustic, RF, infrared,and other wireless media.

Router is typically point of attachment devices on a communicationsnetwork providing IP (packet-based) connectivity between node and othernodes on a network. On a single network linking many computers throughan ad-hoc network of possible connections, router receives transmittedmessages and forwards them to their correct destinations over availableroutes. On an interconnected set of LANs, including those of differingarchitectures and protocols. A router may act as a bridge or link withinLANs, enabling messages to be sent from one to another.

FIG. 1 is a functional block diagram generally illustrative of awireless system 100 which may use an embodiment of the invention. Asshown in FIG. 1, the wireless system may comprise the devices 102, 110A,and 110B. The device 102 may comprise a transceiver 104 having a datalink layer 106 and a physical (PHY) layer 108. In at least someembodiments, the device 102 may implement a first wireless protocol(e.g., 802.11g). Similarly, each of the devices 110A and 110B also maycomprise a transceiver 112A, 112B having a data link layer 114A, 114Band a PHY layer 116A, 116B. In at least some embodiments, the devices110A and 110B may be implement a second wireless protocol (e.g.,802.11n).

FIG. 2 illustrates an exemplary data packet 200 used for wireless datatransmission. As shown in FIG. 2, the data packet 200 may comprise apreamble 202, a header field 204, a Medium Access Control MAC addressfield 206, a data field 208, and a CRC field 210. The preamble 202 maybe used for synchronization and channel estimation. The header field 204may provide modulation information, convolution coding rate information,and data length (i.e., number of octets) information. The MAC addressfield 206 may comprise a hardware address that identifies a node of anetwork. The data field 208 may comprise a variable amount of scrambleddata. The CRC field 210 may comprise information for detecting datatransmission errors.

In accordance with at least some embodiments of the invention, one ormore fields of a data packet 200 may be added and/or modified in orderto permit the devices 110A, 1108 to transmit data to each otheraccording to the second protocol, and permit the devices 110A, 1108 totransmit data to the device 102 using the first protocol and vice versaas previously described. Additionally, adding and/or modifying fields ofa data packet 200 may permit the devices 102, 110A, and 1108 to estimatethe duration of data transfers (used for CCA) according to data ratessupported by either the first protocol or the second protocol.

One method to identify all nodes that support the protocol enhancementsis to use a special Medium Access Control (MAC) address 206 to refer toall such nodes. Nodes that recognize this special address may takespecial action on the frame while the legacy nodes may ignore thepacket. Once a MAC address based method is used, it is important todesign the mechanism such that it does not cause protocol inefficiencydue to a large number of amendments for a particular technology.Efficient address matching for nodes that are enhanced with multipleamendments is also addressed.

Using IEEE 802 as an example, transmissions by 802 based nodes usuallyinclude one or more 6 byte MAC addresses identifying the immediatetransmitter or receiver or previous or later transmitter/receivers etc.The impact of a received frame at a node also depends on the addressescarried in the frames. The 802 MAC address of 0xffffffffffff is wellknown to mean a broadcast address. Similarly multicast group addressesmay be used to identify a group of nodes. Logically, all nodessupporting a particular amendment/enhancement of a particular 802standard may be identified by a multicast group address. However, most802 protocols define a subset of addresses as multicast group addressesand define a specific behavior for packets to/from such addresses. Also,such reserved multicast addresses may require group management torecognize group membership. Unicast addresses in frames are capable ofcausing the most impact on receiving nodes in most protocols.Embodiments of the invention use locally administered unicast addressesto identify all nodes that belong to a particular amendment of atechnology.

Depending on the centralized or distributed nature of a given 802technology, the central co-ordinator or any individual node randomlychooses a locally administered unicast address to identify a particularamendment of the technology. For example, choose a locally administeredMAC address for 11s in an 802.11 network.

If the network is distributed, the chosen address is propagated acrossthe network by whatever mechanism the protocol chooses. If multiple suchchoices are propagated, the largest value is adopted and propagated.

Nodes use the chosen address to imply all nodes that are capable of theparticular amendment. This address may be transmitted in the transmitteror received address or wherever else such address is used. For aparticular network, this locally administered address is now reserved tomean all nodes capable of a particular amendment of the base technology.

A transmitter would send the packet to one of these reserved addressesto indicate that the packet has special significance related to aparticular enhancement/amendment. A device receiving a packet comparesthe receiver address of the packet with its own to determine if it needsto process the packet or not. A device supporting newer amendments wouldalso check the packet against a list of reserved addresses to determineif the packet corresponds to one of the enhancements. If the destinationaddress in the received packet matches one of the reserved addresses,the receiver treats the packet as per the enhanced protocol in theamendment.

This reserved address may be used as the transmitter address also. Thismay imply special meaning for nodes capable of the specific amendment.

Nodes that are enhanced with multiple amendments of an 802 protocol maycheck for each of their amendments while address matching. For example,a WLAN node that is 11s, 11n, 11k, and 11w capable may have to doaddress checking for 4 different addresses.

Efficient coding schemes may be used in the last three bytes to identifythe amendments so that one address matching operation may identify ifthe address implies any of a “n” number of amendments of any of “k”number of technologies. One specific method of doing this is to use amethod similar to Hamming codes.

Once a random address is chosen for a particular amendment, the lastthree bytes of the address are set to all zeros, before it is propagatedin the network. This address becomes the reserved address for theparticular amendment and is propagated in the network.

Addresses set for newer amendments are built on top of the first addressset in the network. The last three bytes of any new addresses set toimply all nodes capable of particular amendments are set as follows:

-   -   The first “F” bits are reserved to increase the number of        amendments that can be covered in the 24 bits space.    -   The last “L” bits identify the amendment to the technology. This        is done via a bit mapping so that “L” amendments may be        identified.    -   If “L” is not enough to cover all amendments to a particular        technology, multiple codes in the first “F” bits may be used to        increase the space. For each such code, the last “L” bits are        bit mapped to identify the amendment.

For most nodes, the scheme defined above may lead to only a singleaddress mapping operation. In severe cases, the number of addressmatching operations might increase to a couple of times. However, itwill still be efficient.

With legacy nodes identified, it may be desirable to silence selectivenodes. Any packet whose duration field is required to be interpreted bynodes may be used to silence them for certain duration by setting theirNAV. In order to selectively change the NAV for nodes belonging toparticular amendments, those amendments may need to understand a newbehavior that over-rides the usual NAV setting behavior. Such behaviormay be specified in all new amendments. A method by which a plurality ofnodes except those belonging to a particular amendment may be silencedfor a time duration is provided.

Selectively silencing using control frames will now be described. Anycontrol frame that does not carry the Basic Service Set (BSS) ID can setthe NAV of all 802.11 nodes that hear it. Specifically a Clear To Send(CTS) frame with any receiver MAC address may be used for silencingnodes. CTS-to-self is an example of one mechanism that uses suchapproach. However, in order to selectively exclude the silencing ofnodes capable of a particular amendment, such nodes need to interpretresetting of the NAV. This involves identification of an indication thata particular amendment is referred.

A method in accordance with an embodiment of the invention is describedby FIG. 4.

802.11 nodes create a random locally administered MAC address andadvertise it as the address that implies a particular amendment. In aninfrastructure BSS, the Access Point (AP) would choose this address.This address is advertised and propagated cross the network in beaconsin an Information Element (IE) with the following information:

-   -   ID    -   Length    -   Number of Amendments identified “n”    -   Amendment identifier 1    -   Locally administered MAC address for Amendment 1    -   Amendment identifier 2    -   Locally administered MAC address for Amendment 2    -   . . .    -   Amendment identifier n    -   Locally administered MAC address for Amendment n

Amendment identifier is a number or ASCII text that identifies whichamendment is being identified with the MAC address that follows it. Ifmultiple addresses are advertised for a particular amendment, the largervalue is accepted and further propagated.

In order to selectively exclude silencing of nodes of a particularamendment, a transmitter sends a CTS frame (or any other control flame)to the MAC address chosen for a particular amendment.

All legacy nodes will reject this frame since it does not match theiraddress. They will also set their NAV to the value specified in the‘Duration’ field of the frame. All nodes that previously decoded the IE,and are capable of the amendment identified by this special address willtreat the frame as if it was unicast to their address. Their NAVs won'tbe updated and they will be free to access the medium usingcontention-based or contention free mechanisms.

Selectively silencing within a BSS using management frames will now bedescribed. Any action frame may be used to set the NAV of an entire BSSand silence them. In order to selectively cause nodes capable of aparticular amendment to not be silenced, an IE in the action frame canbe used to indicate that. The IE format may be as follows:

-   -   ID    -   Length    -   Amendment identifier        Amendment identifier indicates nodes capable of which amendment        are supposed to ignore the NAV setting.

This action frame would be addressed to the same MAC address as thecontrol frame, or be broadcast.

The difference in the two approaches is that the control frame wouldimpact all the nodes in the neighborhood, irrespective of the BSS theybelong to. The management frame would affect only the nodes in the sameBSS as the transmitter. So the control frame could be used to silenceall legacy nodes in a neighborhood, irrespective of their BSS and theaction frame would be used to silence only the nodes within a particularBSS. The former method would be used to ensure priority of WirelessDistribution System (WDS) traffic over BSS traffic and the latter toimplement congestion control.

After the transmission of any of the above two frame types, the nodesthat are not silenced may access the channel and begin a TXOP. Theduration field of such packets may sometimes cause the NAVs of all nodesto be changed (except legacy nodes that are previous to 11e). If such aTXOP ends before the time till which nodes were previously selectivelysilenced, the previously silenced nodes may become active right away. Inorder to silence the nodes again, the previously transmitted packetsused for selective silencing may be transmitted as the last packets ofsuch TXOPs.

Hardware, firmware, software or a combination thereof may be used toperform the functions and operations at the mobile devices in accordancewith the invention. The mobile devices in accordance with the inventioninclude communication devices capable of engaging in at least onedefault radio connection, and at least one auxiliary radio connection.These devices include, for example, mobile phones, PDAs, and otherwireless communication devices, as well as landline computing systemsand communication systems also capable of over-the-air (OTA)communication. A representative example of a mobile device employingprinciples of the invention is illustrated in FIG. 5.

The representative mobile device 800 utilizes computing circuitry tocontrol and manage the conventional device activity as well as thefunctionality provided by embodiments of the invention. For example, theillustrated mobile device 800 includes a processing/control unit 802,such as a Digital Signal Processor (DSP), a microprocessor, reducedinstruction set computer (RISC), or other central processing module. Theprocessing unit 802 need not be a single device, and may include one ormore processors. For example, the processing unit may include a masterprocessor and associated slave processors coupled to communicate withthe master processor.

The processing unit 802 controls the basic functions of the mobiledevice 800 as dictated by programs available in the programstorage/memory 804. The storage/memory 804 may include an operatingsystem and various program and data modules associated with theinvention. In one embodiment of the invention, the; programs are storedin non-volatile electrically-erasable, programmable read-only memory(EEPROM), flash ROM, etc., so that the programs are not lost upon powerdown of the mobile device. The storage 804 may also include one or moreof other types of read-only memory (ROM) and programmable and/orerasable MOM, random access memory (RAM), subscriber interface module(SIM), wireless interface module (WIM), smart card, or other fixed orremovable memory device. The relevant software for carrying out mobiledevice operations in accordance with the invention may also betransmitted to the mobile device 800 via data signals, such as beingdownloaded electronically via one or more networks, such as the Internetand an intermediate wireless network(s).

For performing other standard mobile device functions, the processor 802is also coupled to user-interface 806 associated with the mobile device800. The user interface (UI) 806 may include, for example, a display 808such as a liquid crystal display, a keypad 810, speaker 812, andmicrophone 814. These and other UI components are coupled to theprocessor 502 as is known in the art. The keypad 810 may include alphanumeric keys for performing a variety of functions, including dialingnumbers for I conventional, default cellular communication, and/oreffecting auxiliary radio communication. Other UI mechanisms may beemployed, such as voice commands, I switches, touch pad/screen,graphical user interface using a pointing device, trackball, joystick,or any other user interface mechanism.

The wireless device 800 may also include conventional circuitry forperforming wireless transmissions over the mobile network. A DSP 816 maybe employed to perform a variety of functions, includinganalog-to-digital (ND) conversion, digital-to-analog (D/A) conversion,speech coding/decoding, encryption/decryption, error detection andcorrection, bit stream translation, filtering, etc.

In accordance with the invention, the methods of the embodiments of theinvention may be implemented in a silencing interface 835. Additionally,the communicating mobile devices may include at least one radiocommunication interface that may operate separately or in conjunctionwith the silencing interface 835. The illustrated embodiment includes aBluetooth transceiver 830 for communicating via Bluetooth standards. Awireless LAN (WLAN) transceiver 832 provides for wireless communicationvia a local wireless network, such as in accordance with IEEE 802standards. Any other auxiliary, radio communication interface mayinstead, or in addition, be used in accordance with the presentinvention, as depicted by the respective transceiver 834.

In accordance with the invention, the communicating mobile devicesinclude at least one auxiliary radio communication interface that mayoperate separately or in conjunction with a silencing interface 835. Theillustrated embodiment includes a Bluetooth transceiver 830 forcommunicating via Bluetooth standards. A wireless LAN (WLAN) transceiver832 provides for wireless communication via a local wireless network,such as in accordance with IEEE 802 standards. Messages exchange tosilence nodes in accordance with the invention may be provided by WLANtransceiver 832. Any other auxiliary; radio communication interface mayinstead, or in addition, be used in accordance with the invention, asdepicted by the respective transceiver 834.

A transceiver for cellular communication may also be used. Transceiver818, generally coupled to an antenna 820, transmits the outgoing radiosignals 822 and receives the incoming radio signals 824 associated withthe mobile device 800. For example, signals 822, 824 may represent themessage exchange to silence nodes in accordance with the invention. Thismessage exchange may be conducted via a Radio Access Network (RAN)associated with a cellular network, such as Global System for Mobilecommunications (GSM), Universal Mobile; Telecommunications System(UMTS), Personal Communications Service (PCS), Time I Division MultipleAccess (TDMA), Code Division Multiple Access (CDMA), or other mobilenetwork transmission technology.

It should be noted that any of the transceivers illustrated in FIG. 5may be implemented as a modular transceiver including both transmittingand receiving circuitry, or any of such transceivers may alternativelybe implemented as discrete transmitter and receiver circuits. As usedherein, a “transceiver” is intended to describe circuits or othermodules for wirelessly transmitting and receiving information,regardless of whether the transmitter and receiver circuits are discretecomponents or collectively provided in a single package. I In theillustrated embodiment, the storage/memory 804 stores the various clientprograms and data associated with the present invention. For example,the storage 804 includes an auxiliary interface enable module 836, whichmay include program instructions for enabling power to a particular oneor more of the auxiliary radio communication interfaces. The auxiliaryinterface enable module 836 recognizes that Bluetooth is the desiredauxiliary radio interface, and together with the processing unit 802 maypower on, or otherwise enable for communication, the Bluetooth-relatedcircuitry such as the Bluetooth transceiver 830 to enable its operation.It should be recognized that additional hardware (not shown) to enablepower to such transceivers 830, 832, 834 may also be implemented.

In addition to the various transceiver circuits 830, 832, 834,associated software modules may be provided to assist in the operationof the particular auxiliary radio communication methodology employed.For example, where Bluetooth is the desired auxiliary radio interface, aBluetooth program module 838 may include software operable via theprocessing unit 802 and operable to communicate information via theBluetooth transceiver 530. Similarly, a WLAN module 840 may includeprogram instructions operable via the processing unit 802 and operableto communication information via the WLAN transceiver 832. Thestorage/memory 804 may also include a policy processing module 842 forprocessing policies 844. A parameter processing module 846 may beprovided to process parameters 848 that may be received via the messagesand/or stored at the storage/memory 804.

Communication information may be sent from one communication device toanother communication device(s) via a communication interface 835. Thesilencing interface 835 may be configured to implement embodiments ofthe invention. This includes, for example, sending the information via aGSM/GPRS, TDMA, CDMA, PCS, or any other cellular network infrastructure.

The foregoing description of the exemplary embodiment of the inventionhas been presented for the purposes of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise form disclosed. Many modifications and variations are possiblein light of the above teaching. It is intended that the scope of theinvention be limited not with this detailed description, but ratherdetermined by the claims appended hereto.

1-12. (canceled)
 13. A method for selectively identifying nodesimplementing enhanced version of a protocol standard, said methodcomprising: creating a random locally administered MAC address;advertising to a network said random locally administered MAC address asthe address that implies a particular protocol amendment of the protocolstandard.
 14. The method of claim 13, further comprising: propagatingsaid random locally administered MAC address across a network using aplurality of beacons, in an Information Element.
 15. The method of claim14, further comprising: reserving said random locally administered MACaddress to mean those nodes which are capable of said particularprotocol amendment.
 16. The method of claim 15, further comprising:sending, via a transceiver, a packet addressed to at least a one of thereserved addresses to indicate that the packet has special significancerelated to said particular protocol amendment.
 17. The method of claim15, further comprising: receiving a packet at a receiver; comparing theaddress of the packet with the receivers address and that of thespecially reserved addressed; determining if the receiver needs toprocess the packet or not.
 18. The method of claim 17, furthercomprising: checking the address of the packet against a list ofreserved addresses to determine if the packet has special meaning fornodes capable of one of the protocol enhancements; and treating thepacket as if it was addressed to all nodes capable of the specificprotocol amendment, or as per the enhanced protocol in the protocolamendment, If the destination address in the received packet matches oneof the reserved addresses.